Fuse connection



Feb. 19, 1935. LA MQTTE r AL 1,991,856

FUSE CONNECTION Filed June 26. 1931 FIG.3 FIG. 4 FIG-E) FIGp'i :flrfllurlaflo e fi-fijummer, luvsu'rons I 'WJiWard,

BY T-HEm ATTORNEY atented Feb. 19, 1935 FUSE CONNECTION Application June 26, 1931, Serial No. 546,946

9 Claims.

This invention relates to blasting fuses and more particularly to improvements and means for igniting blasting fuses of the Cordeau type.

Cordeau, as is well known, consists of a small lead tube of approximately the same diameter as double type fuse, filled with an explosive compound which has a velocity of detonation of approximately 17,500 feet per second. Cordeau is used principally in deep well-drill holes and other large blasts. The extreme violence with which it explodes is sufilcient to detonate high explosives lying alongside it in a bore hole and therefore the charge detonates instantaneously throughout its entire length.

While Cordeau has great velocity and strength of detonation, it is very insensitive and cannot be exploded by hammering, pinching, or burning. In actual use it is exploded by blasting caps, or electric blasting caps which must be in actual contact with the explosive compound contained in the Cordeau.

Various methods have been suggested for connecting the branch line" (that portion in the bore hole and extending a foot or more out of it) with the main line which connects all the branch lines but none have proved entirely satisfactory. In general the practice has been to split a section of the branch line of Cordeau for about three inches at the end and pull the split 30 ends apart to form a crotch. The main or trunk line of Cordeau is placed well down in these crotches, and the split ends are wrapped lightly around the main line, one to the right and the other to the left. A blasting cap or electric blasting cap is connected to the end of the main line and fired, thus detonating the whole blast.

This practice has the disadvantage that misfires frequently occur at the connection of the trunk line with the Cordeau line extending into the bore hole, and a. further and particular disadvantage in that such a connection is not waterproof.

An object of our invention is to overcome the disadvantages of prior known methods of firing Cordeau. Another object of our invention is to provide a union between a main line of Cordeau and the line extending out of the blast hole that is not only safe in use but is positive in its function. A further object of our invention is to improve generally upon the use of Cordeau. Other objects will appear as the description proceeds.

These and other objects are accomplished by the following invention in which we have found that a suitable connection can be made for this purpose by providing a shell adapted to be in serted over the end of the branch iuse of Cordeau or the like and having its closed end secured to means adapted to engage the main fuse. This may be accomplished by providing the securing means integral with the closed end of the shell or by providing means on the shell adapted to 5 engage the securing means.

With the view of further illustrating certain embodiments of our invention reference is made to the accompanying drawing in which- Figure 1 shows one form of the connecting means made according to our invention, and consists essentially of a shell 3, enclosing the end of a Cordeau line 2. This shell has a bead at the upper end which engages the clip 4 by inserting the tube 3 through an opening or perforation in the clip until the opening engages the bead. The clip is then ready to be attached to the main Cordeau line 1.

Figure 2 shows another form of connection which comprises a plate of metal having a perforation through which the tube 3 is inserted until the bead on the end of the tube engages the edges of the perforation. The strips 5 and 6 are then wrapped about the main trunk line 1 in the manner shown in this figure. 25

Figure 3 shows a modified form of connecting means comprising a clamp adapted to engage the main trunk line 1, said clamp having fingers 7, adapted to engage a head on the branch line 3'. The band 8 may be moved downward on the fingers '7 as the parts are assembled in order to bring the fingers into close engagement with the bead.

Figure 4 shows a similar arrangement to Figure 3, in which the band 8 is omitted.

Figure 5 shows a modification of the retainer means of Figure 2 in which the free ends may be brought together above the main trunk line 1.

Figure 6 illustrates a form of cap adapted for use with Cordeau fuse having a charge consisting of a primary detonating composition 11, such as fulminate of mercury, and a secondary detonating composition 12 such as tetryl. This cap may also be used with the fulminate or other explosive alone. This cap is adapted to fit over the end of a branch of the Cordeau fuse which may; for example, lead to the blasting charge and may comprise the element 3 in, each of the figures or it may be enclosed within an outer shell which may have the bead at the upper end, as in Figure 1, or spaced from the ends, as shown in Figures 3 and 4. When the blasting cap alone is used the bead for engaging the connecting me ns is provided eith r at the upper end, as

shown in Figure-6, or it may be provided at any point desired.

Figure 7 illustrates an assembly in which the outer shell is used to enclose the blasting cap which is placed over the end of the Gordeau.

The advantages of the various forms of this invention will be apparent to those skilled in the art. The branch connections may be attached at any distance along the trunk line or may be adjusted in position in a minimum of time. A further and particular advantage resides in the fact that these forms of connection are absolutely watertight and after the connections are made may be allowed to remain in position for an extended time even in inclement weather without the possibility of falling rain or melting snow interfering with the operation of the fuse.

For example, by the connecting means illustrated in the drawing the branch line assumes a dependent position from the main line in the same plane and has a tendency by its own weight to remain in this position as shown in the drawing, after the connections are made. In this-position the upper end of the branch line, as well as' the detonating charge in the shell, in such cases where the charge is included, is kept free of water resulting from rain or melting snow. Furthermore, when the fiat closed end of the shell is permitted to abut the main line, as shown in the drawing, a larger surface of the detonating charge in the shell is in close contact with the Cordeau of the main line, and this, to-

gether with the angle of inclination, makes more certain the effect of the detonating wave passing through the main line.

As many apparently widely different embodiments of this invention may be made without departing from the spirit thereof, it is to be understood that we do not limit ourselves to the foreoing examples or descriptions except as indicated in the following patent claims.

We claim:

1. A fuse connection comprising in combination a main line and a branch line of Cordeau, a tubular shell adapted to fit over and engage the free end of the branch line, a bead on the shell, and retaining means having at least two wings, and a perforation between the wings, through which the tubular shell is inserted until the edges of the perforation engagesthe bead.

2. A fuse connector comprising a tube having a closed end, beading on the tube, means having an opening through which the open end of the tube is inserted until the beading engages the opening, and fingers on said means for enaging a fuse line.

3. In a fuse connection, a tube having a closed end and adapted to fit over and engage the end masses of a branch fuse line, a beading on the tube, a clip having an opening therein insufficient in diameter to admit the tube beyond the beading, and means on the clip for securing it to a main fuse.

4. A fuse connection comprising in combination a main line and a branch line of Cordeau, a tubular shell closed at its outer end and adapted to fit over and engage the free end of the branch line, means for securing the tubular shell to the main line and dependent therefrom at an angle of substantially with the longitudinal axis of the shell in a plane with the longitudinal I axis of the main line and with they closed end of the shell abutting the main line to prevent the admission of water to the shell.

5. A fuse connection comprising in combination a main line and a. branch line of Cordeau, a tubular shell closed at its outer end to prevent the admission of water and adapted to fit over and engage the free end of the branch line, a single bead on the shell, and means engaging the bead and the main line for securing them together with the longitudinal axis of the shell in a plane, with the longitudinal axis of the main line and dependent therefrom at an angle of substantially 90, with the closed end of the shell abutting the main line.

6. Afus1=connection comprising in combination a main line and a branch line of Cordeau, a tubular shell having a closed end to prevent the admission of water and adapted to fit over and engage the free end of the branch line, a single bead on the shell, and means comprising a preformed clip adapted to engage the bead and the main line and secure them in contact,

-with the longitudinal axis of the shell dependent therefrom, in a plane with the longitudinal axis of the main line and at an angle of substantially 90 therewith with the closed end of the shell abutting the main line.

'l. A fuse connection comprising in combination a main line and a branch line of Cordeau, a tubular shell containing a detonatirig charge and a booster charge, said shell'adapted to fit over and engage the free-end of the branch line, a single head on the shell, and means comprising a clip adapted to engage the bead and the main line and secure them in contact.

8. The invention of claim 4-, in which a detonating charge is incorporated in the tubular shell.

9. The invention of claim 5, in which a booster charge is incorporated in the tubular shell.

ARTHUR LA MO'ITE. RAYMOND HENRY SUNIMER. .WILLIAM' HILLES WARD. 

